I'm not going to brag, but I've had many lows, long term lows and nothing seems to want to get better. I'm pretty much a wreck at the moment and have been for a while.
Ah, The "joys" of life.
Doesn't seem like bragging at all - but you should seek help. If things are that bad, you need some guidance, my friend, and as much as we are all happy and much obliged to listen and give you our advice, it seems that professional advice might be best for your needs.
And don't give up. Don't ever give up. Life can suck at times, and then it can turn around and amaze you. Without the lows, we cannot truly appreciate the highs. Trust me - I've been there, as I am sure most other people have. Hit rock bottom, and then bounced back up - and it was so much sweeter knowing I stuck in there. Do the same, mate. Chin up.